Remote access to electronic meters using a TCP/IP protocol suite

ABSTRACT

An electronic meter incorporates a TCP/IP protocol suite and an HTTP server to provide two-way access to the meter data. Alternatively, the TCP/IP protocol suite may be incorporated into a gateway serving multiple meters connected through a power line or wireless two-way network. The gateway may incorporate an HTTP server for accessing data from multiple meters and for transmission of data to individual meters. Other aspects of the disclosed system include the use of a common gateway interface for remote access to meter data and to set meter parameters using HTML forms in HTTP browsers; remote reading and setting of multiple meter parameters using a TCP/IP protocol suite; a TCP/IP protocol suite implemented in designated nodes in a CEBus LAN with remote access through TCP/IP to routers and brouters and to individual meters on the LAN; and an SLIP-PPP enabled gateway for remote TCP/IP access through a serial interface to a single or multiple meter parameters.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a CON of Ser. No. 09/975,582 filed Oct. 10, 2001 nowU.S. Pat. No. 6,747,981 which is a CON of Ser. No. 09/022,718 filed Feb.12, 1998 now U.S. Pat. No. 6,396,839.

FIELD OF THE INVENTION

The present invention relates generally to electronic meters andautomatic meter reading, and more particularly to TCP/IP-enabledelectronic meters for remote two-way access over local area networks andwide area networks.

BACKGROUND OF THE INVENTION

The present invention relates to automatic meter reading (AMR) systemsfor use in automatically reading electrical energy and other utilitymeters (e.g., water and gas meters). The invention is more particularlyintended for, although not limited to, use in an electronic meter.Further background information on electronic meters can be found in U.S.Pat. No. 5,548,527, Aug. 20, 1996, titled “Programmable ElectricalEnergy Meter Utilizing a Non-Volatile Memory” (assigned to ABB Power T&DCompany Inc.) Further background on automatic meter reading systems canbe found in U.S. Pat. No. 5,553,094, Sep. 3, 1996, titled “RadioCommunication Network for Remote Data Generating Stations.”

SUMMARY OF THE INVENTION

The present invention, as discussed in greater detail below, involvesthe use of a TCP/IP protocol suite and a hypertext transfer protocol(HTTP) server. The terms “HTTP” and “TCP/IP” are well known in thenetworking and telecommunications arts. For example, TCP/IP refers to awell known set of protocols for linking dissimilar devices acrossnetworks. The invention also involves the use of a “gateway”. A gatewayis a node in a network that connects two otherwise incompatiblenetworks. Gateways may perform code and protocol conversion processes. A“protocol” is a set of rules or procedures relating to the format andtiming of data transmissions between two devices. Protocols typicallybreak a file into equal-size blocks or packets. These are sent and thereceiving device uses a mathematical procedure to determine whether theblock or packet was received accurately.

An electronic metering system in accordance with the present inventioncomprises a wide area network (WAN) operating in accordance with aTCP/IP protocol; a local area network (LAN) comprising a plurality ofmeters each of which includes meter electronics for measuring aprescribed quantity supplied by a utility and memory for storingmeasured data and meter control parameters; a gateway operativelycoupled to the LAN and the WAN; and an HTTP server operatively coupledto the LAN and the gateway, whereby the WAN is provided remote access tothe measured data and control parameters of the meters.

Presently preferred embodiments of the invention further include a CGI(common gateway interface) application coupled to the HTTP server foruse in accessing the measured data. Alternatively, the inventive systemmay include a virtual machine coupled to the HTTP server for use inaccessing the data.

The prescribed quantity is preferably electricity, water or gas.

The HTTP server and CGI application may be embedded in each of themeters or, alternatively, embedded in the gateway.

Other features of the present invention are disclosed below.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 schematically depicts an AMR network comprising a wide areanetwork 10, gateway 20, local area network 30 and meters 40, inaccordance with the present invention.

FIG. 2 schematically depicts an embodiment of the present invention inwhich an HTTP server and a common gateway interface are located in themeter(s) 40.

FIG. 3 schematically depicts an embodiment of the present invention inwhich an HTTP server and a common gateway interface are located in thegateway 20.

FIG. 4 illustrates how the common gateway interface could be replaced bya Java virtual machine and a Java applet.

FIG. 5 portrays an embodiment of the invention in which one or morecomputers are given access to the meters by way of a PPP server orinterface.

DETAILED DESCRIPTION OF ILLUSTRATIVE EMBODIMENTS

The present invention, in one embodiment, employs an electronic meterincorporating a TCP/IP protocol suite and an HTTP server for two-wayaccess to the meter data. In another embodiment of the invention, theTCP/IP protocol suite is incorporated into a gateway serving multiplemeters connected through a power line or wireless two-way network. Thegateway employed in a second embodiment of the present inventionincorporates an HTTP server for accessing data from multiple meters andfor transmission of data to individual meters.

The basic architecture of the present invention is shown in FIG. 1. Asmentioned, embedding an HTTP server and a TCP/IP protocol stack within ameter 40 or a gateway 20 to multiple meters through a local area network(LAN) 30 enables remote access to meter parameters on a continuousbasis. As shown, a set of N meters 40 communicate through a non-TCP/IPtype of LAN 30. The LAN 30 may be, e.g., a CEBus network employing powerline or radio frequency communications (the Consumer Electronics Bus(CEBus) protocol has been adopted as an Electronics Industry Associationstandard (EIA IS-60), and defines a LAN that uses multiple media,including power line, radio, twisted pair, coaxial cable, and infraredsignaling). Also connected to the LAN 30 is a gateway 20 that is alsoconnected to a TCP/IP wide-area network (WAN) 10. Other applications(not shown) are also connected to the TCP/IP WAN 10 and may need toaccess the individual meters or groups of meters. These applicationsaccess individual meters by sending commands contained in packets withattached TCP/IP destination addresses that are unique to each meter.

In the first implementation of the invention (FIG. 2), the gateway 20receives packets from other applications on the WAN 10. The gateway 20includes a TCP/IP interface 22 and a LAN interface 28. The LAN interface28 includes software for transforming the data packets into the formatrequired for transmission on the LAN 30. The gateway 20 then transmitsthese reformatted packets over the LAN 30 to the meters 40. The stepsinvolved in this transformation are:

1. The gateway examines the TCP/IP address of the packet and determinesif it is the address of a meter or meters within the set attached to thegateway through its LAN. If not, the packet is ignored.

2. If the packet is intended for one of the meters on the gateway's LAN,the gateway examines the meter TCP/IP address attached to the packet anddetermines if it is an individual meter address or a broadcast address.

3. If the packet is addressed to an individual meter, then the gatewayencapsulates the packet into a larger packet that is addressed to themeter using its unique LAN address (which is different from its TCP/IPaddress).

4. If the packet is meant for broadcast to all the meters, then thegateway encapsulates the packet into a larger packet addressed to thespecial broadcast address of the LAN (which is different from the TCP/IPbroadcast address).

5. If the packet is larger than the maximum allowable packet size forthe LAN, then the gateway segments the packet into smaller pieces. Eachpiece is labeled with the same LAN address as the original, largerpacket.

6. Each piece of the segmented packet is transmitted onto the LAN forreception by one or more of the meters. The gateway is responsible forreceiving acknowledgments of packet receptions from the meters, and forretransmitting packets if they are not received.

Each individual meter listens on the LAN for packets. A meterreconstitutes the original TCP/IP WAN packet from one or more LANpackets, and then executes the commands contained in the packet andsends the results back to the gateway. The steps involved in thisprocess are:

1. The meter examines the LAN address of the packet to see if it isintended for this meter or is a broadcast address. If the address isneither of these, the meter ignores the packet.

2. If the packet is specifically addressed for the meter, anacknowledgment of reception is sent back to the gateway. If an error isfound in the packet, a negative acknowledgment is sent back to thegateway. For broadcast transmissions, no acknowledgment is sent.

3. The received packet is appended to any previously received pieces ofthe larger segmented packet. When all of the pieces of the segmentedpacket are received, the entire original TCP/IP packet is extracted andsent to the TCP/IP interface software, in the meter.

4. The TCP/IP interface software examines the packet to see what serviceis being requested. In this case, assume the packet is intended forservicing by the HTTP server. (It is possible that there could be otherservers running on the meter to which TCP/IP messages could be sent.)

5. The HTTP server examines the data packet to see what operation isbeing requested. In this case, assume that the packet contains a requestthat an application program be run on the meter to extract its currentreading and send it back to the originator of the request. The HTTPserver will initiate this application through the CGI.

6. The CGI application will query the meter application software to findthe current reading. The meter application directly accesses the meterelectronics to get the required information. The reading is passed backto the CGI application, which writes the reading into a message usingHTML. The HTML message is sent back lo the HTTP server.

7. The HTTP server encodes the HTML message as a TCP/IP packet and sendsit on to the meter's TCP/IP interface.

8. The meter's TCP/IP interface sends the packet to the gateway usingthe same set of steps that the gateway used to send the original requestto the meter.

9. Once the gateway receives the TCP/IP packet from the meter, itretransmits the packet onto the WAN where the originating applicationfor the command can receive it.

In the second embodiment of the invention (FIG. 3), the gateway assumesmost of the tasks assigned to the meters in the first embodiment (FIG.2). The HTTP server 24 and CGI application 26 are moved to the gateway20, and the meters retain only their interface 42 to the non-TCP/IP LAN.The processing of packets received from the WAN 10 proceeds as follows:

1. The gateway examines the TCP/IP address of the packet and determinesif it is the address of a meter or meters within the set attached to thegateway through its LAN. If not, the packet is ignored.

2. The TCP/IP interface software examines the packet to see what serviceis being requested. In this case, assume the packet is intended forservicing by the HTTP server now contained in the gateway. (It ispossible that there could be other server applications running on themeter to which TCP/IP messages could be sent.)

3. The HTTP server examines the data packet to see what operation isbeing requested. In this case, assume that the packet contains a requestthat an application program be run to get the current reading of anindividual meter and send it back to the originator of the request. TheHTTP server will initiate this application through the CGI (26).

4. The CGI application 26 now runs within the gateway. It must determinethe LAN address of the specified meter and send a command packet to itover the LAN.

5. The command is received by the meter and causes the meter applicationto query the electronics to find the current reading.

6. The meter reading is encapsulated into a LAN packet and sent back tothe gateway.

7. The CGI application receives the LAN packet from the meter andextracts the meter reading. The reading is written into an HTML messageand is sent back to the HTTP server.

8. The HTTP server encodes the HTML message as a TCP/IP packet and sendsit on to the gateway's TCP/IP interface 22.

9. The gateway's TCP/IP interface 22 sends the packet onto the WAN 10where the originating application for the command can receive it.

Both implementations of the present invention have been described asusing CGI applications 46, 26 to handle the details of accessing thecurrent reading for a meter. As shown in FIG. 4, the CGI applicationcould be replaced by a Java virtual machine (VM) 26′ running a Javaapplication 26″ that performs the same operations as the CGIapplication.

In addition, both implementations have been described using an examplewhere the current reading of an individual meter is requested by anapplication connected to the WAN. An application on the WAN can alsowrite data to a meter or meters using similar procedures. The data couldmodify parameters affecting the operations of the meter or meters. Anexample would be rate updates.

Either implementation, with their use of TCP/IP and HTTP servers,supports the reading of meters or setting their parameters usingbrowsers such as a Netscape™ or Explorer™. Utilities and homeownerscould perform remote on-demand meter reading via their browsers. Anindividual meter or group of meters could be accessed as if the meter(s)were a web site and their current readings or other data could bedisplayed on the browser. The meters could send forms to the browserthat the user could fill in to change parameters in the meters. Bothreading and updating the meters would be protected by encryption andpasswords.

As shown in FIG. 5, a browser could gain access to the meters through aphone line to a Point-to-Point Protocol (PPP) server 60 attached to theWAN 10 or attached directly to a gateway 20. The PPP server interfaceswith modems (not shown) to provide a TCP/IP link to a browser on theother end of the line. The PPP server sends the packets from the phoneline onto the WAN where they are received by the appropriate gateway. Inthe case of a phone line connection directly to a gateway, the PPPsoftware includes an interface 21 for directly connecting to the TCP/IPWAN interface 22 so that the packets received over the phone line arehandled in the same way as packets received over the WAN 10.

The browser may be replaced by an intelligent application program thataccesses the HTTP server for automated meter reading and parametersetting on a scheduled and repetitive basis. The application uses themeter readings to create or update records in a database. Thisapplication could be a Java application which can interact with the HTTPservers and databases that support the HTTP protocols.

In sum, the present invention includes the following novel aspects: (1)Embedded HTTP server in a meter for on-demand access to meter data andfor remotely setting meter parameters; (2) Embedded HTTP server in agateway to multiple meters to read and set parameters in individualmeters on a LAN; (3) Using CGI for remote access to meter data and toset meter parameters using HTML forms in HTTP browsers; (4) Remotereading and setting of multiple meter parameters using TCP/IP protocolsuite; (5) TCP/IP protocol suite implemented in designated nodes in aCEBus LAN including CEBus routers and brouters with remote accessthrough TCP/IP to the router/brouter and, therefore, individual meterson a LAN; (6) SLIP-PPP enabled gateway for remote TCP/IP access througha serial interface (phone line, or ISDN, for example) to a single ormultiple meter parameters (setting and reading).

The foregoing detailed description of preferred embodiments of theinvention is not meant to limit the scope of protection of the followingclaims. Those skilled in the art of electronic metering will recognizethat many modifications may be made to the presently preferred andspecifically described embodiments without departing from the truespirit of the invention.

1. An electronic metering system, comprising: (A) a wide area network(WAN) operating in accordance with a TCP/IP protocol; (B) a local areanetwork (LAN) comprising a plurality of meters each of which includesmeter electronics for measuring a prescribed commodity supplied by autility and memory for storing measured data and meter controlparameters; (C) a gateway operatively coupled to said LAN and said WAN;and (D) a server operatively coupled to said LAN and said gateway,whereby said WAN is provided remote access to said measured data andcontrol parameters of said meters.
 2. A system as recited in claim 1,further comprising a common gateway interface (CGI) application coupledto said server for use in accessing said measured data.
 3. A system asrecited in claim 2, wherein said server and said CGI application areembedded in each of said meters.
 4. A system as recited in claim 3,wherein each of said meters further comprises a TCP/IP interface.
 5. Asystem as recited in claim 2, wherein said server and said CGIapplication are embedded in said gateway.
 6. A system as recited inclaim 1, further comprising a virtual machine coupled to said server foruse in accessing said data.
 7. A system as recited in claim 1, whereineach of said meters further comprises a LAN interface.
 8. A system asrecited in claim 1, wherein said gateway comprises a LAN interface.
 9. Asystem as recited in claim 1, wherein said gateway comprises a TCP/IPinterface.
 10. A system as recited in claim 1, further comprising acommon gateway interface (CGI) application coupled to said server foruse in accessing said measured data; wherein said server and CGIapplication are embedded in each of said meters; wherein said gatewayand each of said meters comprises a LAN interface and a TCP/IPinterface; and wherein said prescribed commodity is a member of thegroup consisting of electricity, water and gas.
 11. A system as recitedin claim 1, further comprising a common gateway interface (CGI)application coupled to said server for use in accessing said measureddata; wherein said server and CGI application are embedded in saidgateway; wherein each of said meters and said gateway comprises a LANinterface; wherein said gateway further comprises a TCP/IP interface;and wherein said prescribed commodity is a member of the groupconsisting of electricity, water and gas.
 12. An electronic meter,comprising: meter electronics for measuring a prescribed commoditysupplied by a utility; a memory for storing measured data and metercontrol parameters; and a server operatively coupled to said meterelectronics and memory; said electronic meter being configured for usein a system including a wide area network (WAN) operating in accordancewith a TCP/IP protocol, a local area network (LAN), and a gatewayoperatively coupled to said LAN and said WAN, whereby said WAN isprovided with remote access to said measured data and control parametersof said electronic meter.
 13. An electronic meter as recited in claim12, further comprising a LAN interface and a TCP/IP interface operatingin the meter.
 14. An electronic meter as recited in claim 12, furthercomprising a common gateway interface (CGI) application and a meterapplication operating in the meter.
 15. A gateway for use in a systemcomprising an electronic meter connected to a local area network (LAN),the gateway, and a wide area network (WAN) operating in accordance witha TCP/IP protocol, wherein the electronic meter is operatively coupledto the WAN through the gateway, the gateway comprising: a serverembedded in the gateway and operatively coupled to said electronicmeter, whereby said WAN is provided with remote access, via the gatewayto measured data and control parameters of the electronic meter.
 16. Agateway is recited in claim 15, further comprising a LAN interface and aTCP/IP interface embedded in the gateway.
 17. A gateway as recited inclaim 15, further comprising a common gateway interface (CGI)application operating in the gateway.
 18. A method for operating anelectronic metering system, comprising: (A) providing a wide areanetwork (WAN) operating in accordance with a TCP/IP protocol; (B)coupling the WAN to a local area network (LAN) comprising a plurality ofmeters each of which includes meter electronics for measuring aprescribed commodity supplied by a utility and memory for storingmeasured data and meter control parameters; (C) providing a serveroperatively coupled to said LAN; and (D) providing said WAN with remoteaccess to said measured data and control parameters of said meters.